Celebration Becomes Protest Against Czech President

Protesters Hurl Food During Public Unveiling of Velvet Revolution Memorial

PRAGUE—Celebrations here for the 25th anniversary of the fall of communism in the former Czechoslovakia morphed into protests against the Czech president.

At a public unveiling of the Velvet Revolution memorial, protesters booed, whistled and shouted “Resign, resign!” at Milos Zeman. Some protesters even pelted Mr. Zeman with eggs, tomatoes and sandwiches at the event also attended by the presidents of Germany, Poland, Hungary and...